#include <stdio.h>
#include <unistd.h>

int main(int argc, char *argv[]) {
    int opt;
    while ((opt = getopt(argc, argv, "hi:o:")) != -1) {
        switch (opt) {
            case 'h':
                printf("Usage: %s [-h] [-i input] [-o output]\n", argv[0]);
                break;
            case 'i':
                printf("Input file: %s\n", optarg);
                break;
            case 'o':
                printf("Output file: %s\n", optarg);
                break;
            default: /* '?' */
                fprintf(stderr, "Usage: %s [-h] [-i intput filename] [-o output filename]\n", argv[0]);
                return 1;
        }
    }

    return 0;
}

